<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			var a = 3.14;
			var b = a+"";
			console.log(typeof b);
			if(b.indexOf()!==1){
				console.log(a+"是小数");
			}else{
				console.log(a+"不是小数");
			}
		</script>
	</body>
</html>
